Finding Solutions for the Klamath Basin

As part of an ongoing effort to improve water conditions and fish habitat in the troubled Klamath Basin, Oregon Trout worked with U.S. congressman Greg Walden (R-OR) to pass the Chiloquin Dam Fish Passage Feasibility Study Act. The bill will provide federal funding for “a study of the feasibility of providing adequate upstream and downstream passage for fish at the Chiloquin Dam” including “review of all alternatives for providing passage…determination of the most appropriate alternative and development of recommendations for implementing that alternative.”

In studies conducted by the Oregon Fish and Wildlife Department, the Bureau of Reclamation and the Klamath Tribes, Chiloquin dam was found to be a major obstacle to upstream and downstream fish migration. The fish ladders on the dam are outdated and almost completely nonfunctional. The U.S. Fish and Wildlife Service estimated that the dam currently blocks 95% of the viable sucker spawning habitat on the Sprague River.

“The sucker fishery and the condition of Upper Klamath Lake are bellweather indicators of the overall health and water quality of the Upper Basin ecosystem and the Basin’s ability to provide a sustainable livelihood for everyone.” –Klamath Tribes Report

Originally built by the Bureau of Indian Affairs, the sole purpose of the Chiloquin dam is to provide water to the Modoc Point Irrigation District (MPID). Regardless of the recommendations of the study, the MPID will be able to draw water from diversion pumps on the river. In the summer of 2001, 140 farmers were denied water from the Klamath Irrigation Project to protect the imperiled mullet1 and coho populations. Any action to increase fish passage could help prevent future water shutoffs by helping to restore healthy mullet populations in Upper Klamath Lake and flow potential to the Klamath River.

A thorough and comprehensive assessment of all possible methods to increase fish passage is the crucial next step toward formulating an action plan for the dam. Oregon Trout recognizes that the Chiloquin dam is detrimental to valuable populations of native fish and that something must be done to provide adequate passage. This study is a strong first step toward that goal. Oregon Trout will wait for the completion of the study before forming a habitat recovery plan to restore strong runs of native fish on the Sprague River.


1—Mullet, in the form of Lost River (deltistes luxatus) and shortnose sucker (chasmistes brevirostryus), were the freshwater species at issue.